Diamond cutting and polishing device



July 23, 1963 B. DEMBINSKI DIAMOND CUTTING AND POLISHING DEVICE 2 Sheets-Sheet 1 Filed Jan. 18, 1961 w m m July 23, 1963 B. DEMBINSKI DIAMOND CUTTING AND POLISHING DEVICE 2 Sheets-Sheet 2 Filed Jan. 18, 1961 Kiwi United States Patent 3,098,326 DIAMGND CUTTING AND POLISHING DEVICE Berek Dembinski, 368 Brooklyn Ave., Brooklyn, N.Y. Filed Jan. 18, 1961, Ser. No. 83,410 Claims. (Cl. 51125) This invention relates generally to a diamond cutting, grinding and polishing device and is particularly concerned with a diamond cutting, grinding and polishing device which is adapted for predetermined, automatic termination of its operation.

It has been found in practice that conventional diamond cutting, grinding and polishing equipment is difficult to adjust so as to limit precisely the operations accomplished thereby and so as to be adaptable to handling a wide range of gems of varying weights. More specifically, while some attempts have been made for automatically limiting the amount of such cutting, grinding and polishing, it has been found that these attempts have achieved only approximate limitation of such operations and that under certain conditions substantial departures from the intended depth of cutting, grinding and polishing are encountered.

The present invention overcomes these difficulties and is adaptable not only for the performance of such operations with regard to diamonds, but may also be used for the cutting, grinding and polishing of other gems.

More specifically, it is an object of the present invention to provide an improved diamond cutting, polishing and grinding machine which is capable of precisely limiting the amount of such operations to which the diamond secured in such machine is exposed.

Another object of the invention is to provide an improved means for diamond cutting, grinding and polishing which will prevent the diamond secured by said device from being over-exposed to such operations.

Another object of the invention is to provide an electrically operated device of the character indicated which will automatically limit its operation in the event of a power failure.

Another object of the present invention is to insure withdrawal of the diamond secured thereby from exposure to the cutting, grinding and polishing operations in the event of the aforesaid power failure.

A further object of the present invention is to provide a device of the character indicated which is adapted to precise cutting, grinding and polishing of a great range of gems of varying weights.

A further object of the invention is to provide a device of the character indicated whose capacity for limiting the aforesaid operations of grinding, cutting and polishing is substantially independent of the weight of the stone secured by said device and of the stone securing means employed therein.

A further object of the present invention is to provide a device for automatically cutting, polishing and grinding operations which may be successively accomplished on the same stone, on which different facets of the same kind can be formed in perfect symmetry without any need for readjustment or reading of the calibrated scale employed therein for limiting the depth of cut.

Where special conditions or imperfections are present on a particular stone so as to require increase or decrease in the size of the facets thereof, it is an object of the present invention to provide calibration means which may be used to aid in resetting the allowable limit for the depth of cut of such facets and for thereafter returning to the normal depth of out.

A still further object of the present invention is to provide a device for cutting, polishing and grinding precious and semi-precious stones, which device is of simple con- Patented July 23, 1963 struction, dependable in operation and capable of easy and precise operation, whereby said stones may be accurately cut, ground and polished to predetermined degrees.

Other and further objects of the present invention will become apparent from the following description as read in connection with the accompanying drawings.

In the drawings:

FIGURE 1 is a side elevation of one form of the pres ent invention;

FIGURE 2 is a plan view of said form of the invention;

FIGURE 3 is a rear view of the mechanism contained in the housing provided in said form of the invention; the said housing being shown with its cover removed, the said cover being turned so as to make visible its inner face;

FIGURE 4 is a view depicting the mechanism contained in said housing and showing two operative positions thereof;

FIGURE 5 is a detailed view depicting the operation of the solenoid operated trigger employed in said mechanism;

FIGURE 6 is a fragmentary view taken about the line 66 of FIGURE 3;

FIGURE 7 is a fragmentary view taken about the line 7-7 of FIGURE 4; and

FIGURE 8 is a diagram depicting the electrical circuit which is employed to operate the said form of the invention.

As may be seen in FIGURES 1 and 2 of the drawings, one embodiment of the invention comprises means for holding a diamond in contact with a rotating surface such as that presented by a cutting, grinding or polishing, abrasive wheel, said wheel being designated by the numeral 10 and said means for holding the diamond being of conventional design and designated generally by the numeral 11. The diamond holding means is supported by an overhanging arm 12 which, as may also be seen in FIGURES 3 and 4 of the drawings, rests against a roller 13, which is rotatably supported at one end of an inclined control arm generally designated by the numeral 14. The control arm 14 is secured within a housing including front and rear covers, designated respectively 15 and 16. This housing is vertically adjustable and securable by means of thumbscrew 17 which is engageable with a vertical shaft 18 received within a vertical aperture 18a formed at one end of a horizontal member 19 and supported upon a base 20. The housing is also supported upon a suitable surface '70 by means of an adjustable threaded member 21 provided in said base 20. The overhanging arm 12 is provided with an extension 22 which is abuttable against the side of a second vertical shaft 23 secured in said base 29, thereby limiting the rotary motion of the overhanging arm 12 which tends to be induced by the movement of the aforesaid cutting, grinding and polishing wheel. The overhanging arm 12 is also vertically adjustable by rotation of an adjustable thumbscrew 24 which is abuttable against a yoke 25 suit-ably supported by a vertical member 26 adjustably secured in an elongated slot 27 provided in the base 20, the said thumbscrew 24 being threadedly engaged with the overhanging arm 12. The foregoing arrangement permits adjustment of the diamond with respect to the wheel 10 vertically and radially and also permits secure maintenance of said adjustment in any desired abutting position upon said wheel 10, the arm 12 being abuttable against the roller 13 so as to depress said roller 13 in correspondence with the vertical movement of said diamond during the cutting, grinding or polishing operation performed by the wheel 10, the said arm 12 and roller 13, as shown in FIGURE 4, being movable, for example, during the performance of said operation from the position depicted in said FIGURE 4 in solid lines to the position depicted therein in broken lines and designated respectively by the numerals 12a and 13a.

In performing any of the aforesaid operations of cutting, grinding or polishing of the diamond by the wheel 10, a hammer 26 pivotably supported within the housing about a pin 27 and biased by a torsion spring 28 anchored in an aperture 29 in said cover is rotated into engagement with a vertically depending latch 38 rotatably supported upon a pin 31 secured to said housing, the hammer being provided with a pin 26a engageable with a slot 32 formed in said vertical depending latch 39. After the hammer 26 is initially cocked by engagement of the pin 26a with the slot 32, the diamond is brought into contact with the wheel 10 and cut, ground or polished to any desired depth, thereby depressing the overhanging arm 12 and roller 13 as to the positions designated by the numerals 12a and 13a in FIGURE 4 and pivoting the control arm 14 so as to bring an offset end portion thereof, designated by the numeral 14a, into a raised position. At this time, a calibrated adjusting knob 34 provided upon the outer face of the front cover 15 is rotated so as to bring a rotor pin 35 provided at the end of a rotor arm 36 into contact with the said offset portion 14a, the said rotor arm being rotatable by a shaft 37 connected with said knob 34. Upon making said contact between rotor pin 35 and the ofiset portion 14a, a yellow indicating light 38 is actuated, the said yellow indicating light being provided in a housing generally designated by the numeral 39. It will be noted that during the aforesaid oporation, a switch 40 provided in said housing and indicated upon the circuit diagram illustrated in FIGURE 8, is closed so as to permit the flow of current through said circuit, the said switch 40 being connected to a 110-voltage supply. So also, during the said operation a double-pole, double-throw switch 41 is engaged with terminals 41a and 41b to permit actuation of the circuit comprising said yellow indicating light 38 which is connected with a 6-volt portion 42a of the step-down side of a transformer designated in said circuit diagram by the numeral 42, the said transformer also including a transformer coil 43 forming part of the 110-volt circuit closed by the switch 40. The total voltage across the step-down coil of the transformer is preferably 18 volts.

When the yellow indicating light 38 is actuated, the circuit containing said yellow indicating light is opened and the double-pole, double-throw switch 41 is then engaged with terminals 44 and 45 simply by disposing said switch 41 in a downward position. This disposition actuates a green indicating light 46 provided in said transformer housing 39, said green indicating light also being connected with said 6-volt portion 42a of the step-down side of the transformer 42 and being a convenient means for advising the user of the unit presently described that said unit is available for use in automatically limiting the depth of any further desired cutting, grinding or polishing of the diamond to the depth thereof originally attained during activation of the aforesaid yellow indicating light. It will be noted that to accomplish the actuation of the green indicating light 46, it is necessary for a flanged plate 47 supported upon the hammer 26 and functioning as a single-pole, double-throw switch to be brought into contact with a vertically movable plunger 48 so as to raise said plunger 43 to a position wherein it closes the circuit which includes the green indicating light 46, that portion of switch 41 which contacts terminal 45, and the aforesaid 6-volt portion of the step-down side of the transformer, as is shown in the circuit diagram of FIGURE 8.

After the green indicating light 46 is actuated, the diamond is turned to the desired position from which it is intended to commence the next operation of cutting, grinding or polishing thereof, the rotor arm 36 being left in the position which it reached when it initially made contact with the aforesaid offset portion 14a of the control arm 14. It will be noted that upon the repositioning of said diamond, the contact between said offset portion 14a and the rotor pin 35 is broken. Cutting, grinding or polishing of the diamond will continue by virtue of the rotation of the wheel 10 until said offset portion 14a contacts the rotor pin 35. At this time, it will be seen, from the circuit diagram of FIGURE 8, that such contact will short-circuit the transformer 42, the said rotor arm 36 being connected in parallel with said transformer by way of that portion of switch 41 which contacts terminal 44. Said transformer is also connected in parallel with a solenoid 50 disposed within the housing and supported upon the front cover 15 thereof as shown in FIGURES 3 and 4, the solenoid 50 retaining a trigger 51 against the bias of a tension spring 56, said trigger 51 being engaged with the latch 30. The tension spring 56 is anchored by a screw 57, secured in a cross-member 58 mounted upon the housing 15 and is engaged with a pin 59 provided upon the vertical depending latch 30. Upon the aforesaid short-circuiting, the trigger 51 is released by the solenoid, and the spring 56 swings the vertical depending latch 30 out of engagement with the pin 26:: of the hammer 26. Since the torsion spring 28 urges said hammer 26 in a downward direction, the latter strikes a pin 14b provided upon the control arm 14 thereby lifting the overhanging arm 12 out of contact with the wheel 16. Since the impact of the hammer 26 is sharp and quick, the diamond is quickly withdrawn from contact with the aforesaid Wheel 10, thereby insuring a termination of the cutting, grinding or polishing operation which would otherwise continue to be performed thereon, the control arm assuming the position depicted most clearly in FIGURES 3 and 6. At the same time, the flanged plate 4 7 is withdrawn from the plunger 43 so as to open the circuit containing the green indicating light. Such withdrawal also accomplishes a contact between said plunger 48 and terminal connected with red indicating light 80, which is mounted on the transformer housing 39 and which is activated by said plunger contact, the plunger 48 being biased towards the downward position depicted in FIGURE 3, this position correspond ing with closure of the circuit containing said red indicating light. In this way, the termination of said grinding, cutting or polishing operation will be indicated by the activation of the red light 80.

It will be noted that an important feature of the invention resides in the fact that not only will said impact of the hammer 26 be accomplished upon a short-circuiting of the transformer 42, but that similarly, in the event of power failure occurring in the llO-volt circuit and reflected in the step-down portion of the transformer 42 will similarly act to release the trigger 51 so as to permit the spring 56 to withdraw the diamond from the wheel 10 in the aforesaid manner. Thus, any risk of excessive cutting, grinding or polishing which may otherwise be run 'by reason of a defective circuit, is obviated.

It will also be noted that the control arm 14 is engagcd with a tension spring 53 anchored to a pin 54 supported by the cover 15. This spring 53 functions as an additional aid in pivoting the control arm so as to maintain contact with the overhanging arm 12 and thereby assure at all times that the depth of cutting, grinding or polishing of the diamond is determined by the position of the control arm 14. At the same time, said spring 53 also aids in accelerating the downward motion of said control arm when its pin 14b is struck by the hammer 26 after release of the solenoid actuated trigger 51.

It will also be seen that due to the potential sharpness of the impact of said hammer 26, as well as the bias of the spring 28, which may be selected as desired, acting together with the tension spring 53, a wide variety of diamonds and other stones of varying masses may be formed with the aid of the above-described device. The tendency of the control arm 14 towards downward movement, by reason of the impact of the hammer 26 and the force exerted thereon by the tension spring 53, is not substantially affected by substantial increase in the mass of said stones, nor by the inertia which might otherwise accompany such increase in mass and reflect itself in a sluggishness of operation of the limiting mechanism.

It will also be noted that the hammer 26 may easily be set in engagement with the vertical member 30 by means of a cocking arm 6%), which is pivotably supported within the housing by a screw 61 threadedly engaged with the rear cover 16. Said cocking arm 66 rests at one end upon a nut 62 mounted upon a stud 63 engaged with said cover 16 and is provided with a transverse pin 64 abuttable against the pin 26a of the hammer 2 6 so as to raise said hammer 26 into a position whereby the transverse pin 26a will be seated within the slot 32, as may be seen most clearly in FIGURES 4 and 7. The cocking arm 60 is normally maintained in the inclined position depicted in FIGURE 3 by means of a tension spring 65 anchored upon a screw 66 engaged with the rear cover 16, the said spring also being engaged with a transverse aperture 67 provided in the said cocking arm. The latter also projects externally of the housing and terminates in a handle 60a which may be manually engaged and depressed when cocking of the hammer 26 is desired.

It will be seen from the foregoing that the abovedescribed device is easily operable, that it automatically limits the cutting, grinding or polishing of the diamond or other stone abutting against the rotatable wheel and that it insures against excessive removal of the substance of said diamond or other stone. Since the knob 34 is calibrated in units of depth of cut, it may be accurately set to limit said cutting, grinding or polishing operation, as desired. Moreover, by reason of its calibrations, the same cutting, grinding or polishing operation may be successively accomplished on different facets of the same stone and thereafter repeated at subsequent stones held by the stone supporting means 11.

The embodiment of the invention illustrated and described hereinafter has been selected for the purpose of clearly setting forth the principles involved. It will be apparent, however, that the present invention is susceptible to being modified in respect to details of construction, combination and arrangement of parts which maybe resorted to without departure from the spirit and scope of the invention as claimed.

I claim:

1. A diamond abrading device comprising, in combination, a rotatable abrasive wheel, means for holding a diamond in contact with said abrasive wheel, said diamond-holding means being provided with a vertically movable arm engaged With an inclined control arm pivotably supported in a housing, said control arm being contactable with presettable means corresponding with a predetermined depth of cut of said diamond, the said housing also being provided with a solenoid energized 5 while said control arm is withdrawn from contact with said pre-settable means, a trigger being retained within said solenoid during energization thereof, the said trigger supporting a vertically depending latch engaged with a spring-biased hammer while said trigger is retained Within said solenoid, the said solenoid being de-energized upon contact between said control arm and said presettable means, whereby said trigger releases said latch and said latch is withdrawn from engagement with said spring-biased hammer, the said latch being urged out of said engagement with said spring-biased hammer by spring means anchored within said housing, the said hammer striking said control arm upon said disengagement with said latch, whereby said control arm raises said vertically movable arm of said diamond-holding means and withdraws said diamond from said abrasive wheel.

2. A device according to claim 1, said spring-biased hammer being engageable with a pivotable cocking arm extending within said housing and manually engageable exteriorly of said housing, said spring-biased hammer being raisable by said cocking arm into engagement with said latch.

3. A device according to claim 2, said pre-settable means being part of a circuit including electrical indicating means actuated during the initial abrasion of said diamond, said spring-biased hammer being provided with switch means for closing a second circuit including a second electrical indicating means, said last-mentioned circuit being closed during engagement of said springbiased hammer with said latch, said switch means also opening said second circuit and closing -a third circuit including a third electrical indicating means when said spring-biased hammer is released from engagement with said latch and strikes said control arm.

4. A device according to claim 3, the said solenoid being connected in parallel with a supply of electricity to each said circuit and being short-circuited upon contact between said control arm and said pre-settable means, whereby said solenoid is de-energized.

5. A device according to claim 1, the said housing being provided with a horizontal member provided with at least one vertical aperture, a vertical shaft being received in said vertical aperture and supported upon a base, the said vertical shaft being engageable by clamping means disposed transversely of said aperture, whereby the said housing and control arm are securable in a plurality of verticaly adjusted positions.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A DIAMOND ABRADING DEVICE COMPRISING, IN COMBINATION, ROTATABLE ABRASIVE WHEEL, MEANS FOR HOLDING A DIAMOND IN CONTACT WITH SAID ABRASIVE WHEEL, SAID DIAMOND-HOLDING MEANS BEING PROVIDED WITH A VERTICALLY MOVABLE ARM ENGAGED WITH AN INCLINED CONTROL ARM PIVOTABLY SUPPORTED IN A HOUSING, SAID CONTROL ARM BEING CONTACTABLE WITH PRESETTABLE MEANS CORRESPONDING WITH A PREDETERMINED DEPTH OF CUT OF SAID DIAMOND, THE SAID HOUSING ALSO BEING PROVIDED WITH A SOLENOID ENERGIZED WHILE SAID CONTROL ARM IS WITHDRAWN FROM CONTACT WITH SAID PRE-SETTABLE MEANS, A TRIGGER BEING RETAINED WITHIN SAID SOLENOID DURING ENERGIZATION THEREOF, THE SAID TRIGGER SUPPORTING A VERTICALLY DEPENDING LATCH ENGAGED WITH A SPRING-BIASED HAMMER, WHILE SAID TRIGGER IS RETAINED WITHIN SAID SOLENOID, THE SAID SOLENOID BEING DE-ENERGIZED UPON CONTACT BETWEEN SAID CONTROL ARM AND SAID PRESETTABLE MEANS, WHEREBY SAID TRIGGER RELEASES SAID LATCH AND SAID LATCH IS WITHDRAWN FROM ENGAGEMENT WITH SAID SPRING-BIASED HAMMER, THE SAID LATCH BEING URGED OUT OF SAID ENGAGEMENT WITH SAID SPRING-BIASED HAMMER BY SPRING MEANS ANCHORED WITHIN SAID HOUSING, THE SAID HAMMER STRIKING SAID CONTROL ARM UPON SAID DISENGAGEMENT WITH SAID LATCH, WHEREBY SAID CONTROL ARM RAISES SAID VERTICALLY MOVABLE ARM OF SAID DIAMOND-HOLDING MEANS AND WITHDRAWS SAID DIAMOND FROM SAID ABRASIVE WHEEL. 